Fire extinguishing apparatus



Oct. 31, 1939. P. A. STQVER 2,177,963

FIRE EXTINGUISHING APPARATUS Filed June 28, 1937 FIB- l IB E INVENTOR. pau/ 4. 5/0V/ ATTORNEY.

Patented Get. 31, 1939 PATENT QFHQE FIRE EXTINGUISHING APPARATUS Paul A. Stover, San Francisco, Calif., assignor to Fire-Gard Corporation, ,San, Francisco, Calif., a corporation of Nevada application June 28, 1937, Serial No. 150,739

'7 Claims.

This invention relates generally to apparatus capable of functioning to automatically extinguish fires. It. is of the type making use of fire extinguishing liquid, like carbon tetrachloride,

A which is released when a certain part of the apparatus is heated to an elevated temperature.

It is an. object of the invention to provide a practical apparatus of the above character, capable of installation in ceiling recesses, without seriously marring the appearance of the ceiling surface.

Another object of the invention is to provide a concealed type of fire extinguishing apparatus which will be certainto release in the event of fire, and which after release will discharge a shower of fire extinguishing liquid.

Another object of the invention is to provide improved means for effecting release of fire extinguishing liquid, which will have an abrupt releasing action, without making use of springs, weights, or like biasing means.

,Furtherobjects of the invention will appear from the following description in which the preferred embodiment of the invention has been set forth in detail in conjunction with the accompanying drawing.

Referring to the drawingzi 'Fig. 1 is a side elevational View, partly in cross- 1 section, illustrating apparatus incorporating the present invention installed in a ceiling recess.

Fig. 'Z'is a cross-sectional view taken along the line 2--2 of Fig. 1. I

Fig. 3 is a cross-sectional detail taken along the line 33 of Fig. 1. A

Fig. 4 is an enlarged cross-sectional detail showing details of the releasable closure.

In general the present apparatus makes use of mounting means adapted to be disposed with- .in a ceiling recess. Detachably secured to this mounting means there is. a cartridge which carries fire extinguishing liquid like carbon tetrachloride, and also means whereby this liquid is automatically released in the event of fire. Referring now to the drawing-the mounting means is designated generally by numeral Ill, and the cartridge by numeral l l. The representative type of mounting means illustrated consists. of an annular adapter ring l2, formed of sheet metal. This ring is shown disposed within a recess formed in the ceiling l3, and its lower face is provided witha flange it, which is flush with the lower ceiling surface it. Flange I4 is shown engaging the spacers H, which are of a length commensurate with the thicknessof the ceiling plaster. Screws H3 or like means serve to retain the adapter ring in proper position.

The cartridge means ll consists of a container l9, preferably of-the conventional sheet metal type, commonly referred to as tin cans. The lower end 20 of this container is provided with a plurality of perforationstl. Extending over the outer face of the end wall 28, there is a Wall 22 of light sheet metal which is of slightly larger diameter than the diameter of the can. Periph- 10 eral edge portion 23 of the wall 22 is sealed with respect to the adjacent periphery of the can, by means offusible solder 26. Assuming that conventional practice is used in forming the end wall 20 of the can, this wall is provided with annular corrugations, as illustrated particularly in Fig. 1. The closure wall 22 is. likewise corrugated so that it nests with the corrugations in the end wall 20, so that a minimum amount of interveningispace is provided.

To facilitate attachment of the cartridge with the mounting means it, I have shown the upper endof the adapter ring 12 provided with an inturned flangeu25. Attached to the periphery of the container Hi there is a sheet metal band it, spaced portions ofwhich are folded to form tabs 21. Flange .25 is provided with circumferentially spaced slots.28,. through which the tabs 2i may pass; --.Thus1in applying the cartridge ll tabs 21 are registered .with the slots 28 and after the,

containerhas been elevated to aposition with the tabs 21 above the flange 25, the container is turned so ,that the tabs 27 may rest upon the upper faceof the flange 25.

In .orderto enhance the appearance of the apparatus, and in order to conceal the major parts of theapparatusfrom view, a cover plate 29 is provided which is foraminated as by means of louvers '31.. Instead of directly attaching this cover plate to the fixed parts of the apparatus, it is attached only to the closure plate 22, as by means of a screw 32. Thus when the closure plate 22 is released by melting of the fusible metal alloy 24, this plate together with the cover plate 29 drops clear of the apparatus.

Operation of my apparatus can be described as follows: In the event of a fire in a room in which the apparatus is installed, the closure plate 22 is heated by hot gases passing upwardly through the louvers in plate 29, and also to some extent by absorption of heat of radiation. Heat absorbed by plate 22 raises the temperature of the fusible metal alloy 24 and at the same time increases the internal pressure upon the plate 22. Such increase in'internalpressure can be better explained by reference to Fig. 4. It will be evident that in attaching the closure plate 22 to the lower end of the can a small amount of clearance exists between the upper surface of this plate and the lower surface of the end wall 20. This space is in communication with the interior of the can, and therefore when the can is in normal inverted position as shown in Fig. 1, the space is filled by a comparatively thin film of fire extinguisher fiuid. Carbon tetrachloride or like fire extinguisher fluid is comparatively volatile, and its vapor tension increases rapidly with increasing temperature. Therefore direct heating of the above mentioned film of fire extinguisher liquid, causes a rapid increase in internal pressure upon the closure plate 22, before sufllcient heat has been absorbed to generally heat the liquid contents of the can. By the time the temperature of the fusible alloy 24 attains its melting point, a considerable internal pressure urges the closure plate 22 towards released position. Thus the closure plate is virtually blown from the lower end of the can, with explosive violence, without the use of supplemental biasing means such as compression springs. Since the cover plate 29 is attached to the closure plate 22, release of the closure plate causes not only this plate but also the cover plate 29 to drop to the floor of the room. Fire extinguisher liquid now sprays downwardly from the bottom of the can, to extinguish the fire in a manner well known to those skilled in the art. After the contents of the can have been thus discharged, it is a simple matter to remove the can or cartridge from the adapter ring l2, and to apply a new cartridge together with a sealed closure plate.

Mention has been made of the fact that with the attachment described between the cover plate 29 and closure plate 22, the closure drops down to the floor of the room when the closure plate 22 is released. If the cover plate 29 were directly attached to the adapter ring I2, without the attaching means 32, the closure disk 22 would merely drop down upon the under side of the cover plate 29, and the fire extinguisher liquid would first strike the closure 22 and the cover plate, and thereafter drip down from the cover plate. It has been found that such dripping of the fire extinguisher liquid is not as effective as a sprinkling or showering action, such as is obtained by direct downward discharge of liquid from the perforations 2|.

My apparatus can be readily installed in various buildings, either at the time the building is being constructed, or in pre-existing structures. The apparatus will not interfere with the aesthetic or decorative value of a room, because only the cover plate 29 is visible, and this can be painted or finished to correspond with the finish on the remainder of the ceiling surface.

I claim:

1. In fire extinguishing apparatus, mounting means adapted to be disposed within a ceiling recess, and cartridge means adapted for detachable connection with said mounting means within said recess, said cartridge means comprising a sheet metal container for fire extinguishing liquid like carbon tetrachloride, said container having permanent upper and lower end walls, the lower end wall having a plurality of perforations, a supplemental closure of sheet metal extending over said perforated end wall, and in relatively close proximity to the same, whereby a relatively thin layer or film of fire extinguishing liquid occupies the space between said closure and the adjacent end wall, and fusible metal alloy serving to seal the peripheral edge portion of said closure with the adjacent peripheral portion of the container.

2. In fire extinguishing apparatus, a container for volatile fire extinguishing liquid like carbon 5 the container through said perforations.

3. In fire extinguishing apparatus, mounting means adapted to be disposed within a ceiling recess, cartridge means adapted for detachable connection with said mounting means, whereby the cartridge means is likewise disposed within the sealing recess, said cartridge means including a container for fire extinguishing liquid, said container having perforations in its lower end through which fire extinguishing liquid may shower, a releasable closure for said perforations, fusible alloy serving to seal said closure with respect to said container, a foraminated cover plate extending over the front side of the mounting, and means serving to connect said cover plate to said closure, said last means forming the sole retention means for said cover plate, whereby when said closure is released by fusion of said alloy said closure together with said cover plate is permitted to drop clear of the assembly.

4. In fire extinguishing apparatus, mounting means adapted to be disposed within a ceiling 1 recess, cartridge means adapted for detachable connection with said mounting means whereby the cartridge means is likewise disposed within the ceiling recess, said cartridge means including a metal container, said metal container having apermanent lower end wall having perforations through which liquid may shower, said cartridge also including a releasable closure extending over the lower end of the container and sealed with respect to the container by means of fusible metal alloy, a foraminated cover plate extending over the front side of the mounting, and means serving to attach the cover plate to said releasable closure, said means forming the sole means for retaining said cover plate in position.

5. In fire extinguishing apparatus, an adapter ring adapted to be disposed within the ceiling recess, a cartridge containing fire extinguishing liquid and adapted for detachable connection with said adapter ring whereby the cartridge is likewise disposed within the ceiling recess, said cartridge including a substantially cylindrical metal can containing fire extinguishing liquid, the can being normally in a vertical position and having its lower end provided with perforations; a sheet metal closure extending entirely over the lower end wall of the container and having its peripheral edge portion sealed with respect to the periphery of the container, by means of fusible metal alloy, a foraminated cover plate extending over the front side of the adapter ring, and a member serving to connect the cover plate with said closure, said member forming the sole means for retaining said cover plate in normal position.

6. In fire extinguishing apparatus, a container for relatively volatile fire extinguishing liquid like carbon tetrachloride, perforations in one wall of the container through which the liquid may sprinkle, a closure extending over said wall and having a peripheral portion thereof sealed withrespect to the wall by a fusible metal alloy, whereby a space of relatively small volume but relatively large area is formed between the closure of the wall which is in communication with the interior of the container through said perforations, the alloy having a temperature of fusion such that when the alloy is fused by application of heat, the vapor pressure of the carbon tetrachloride in said space causes removal of the closure plate with explosive violence.

7. In fire extinguishing apparatus, a sheet metal container for relatively volatile fire extinguishing liquid like carbon tetrachloride, said container having cylindrical shaped side walls and substantially fiat end walls attached to the side walls by crimped annular edges, perforations in one end wall of the container through which the liquid may sprinkle, a sheet metal closure disc extending over said end wall and having a peripheral portion thereof sealed with respect to the end wall by a fusible metal alloy, the seal being on an annular area. adjacent the crimped edge which attaches said one end wall to the side wall, said closure disc being in close proximity with said end wall whereby a space of relatively small volume but relatively large area is formed between the closure and said end wall, said space being in communication with the interior of the wall through said perforation, the alloy having a temperature of fusion such that when the alloy is fused by application of heat the vapor pressure or" the carbon tetrachloride in said space causes removal of the closure plate with explosive violence.

PAUL A. STOVER. 

